ggseqfplot {ggseqplot}

Sequence Frequency Plot

Description

Function for rendering sequence index plot of the most frequent sequences of a state sequence object using ggplot2 (Wickham 2016) instead of base R's plot function that is used by TraMineR::seqplot / TraMineR::plot.stslist.freq (Gabadinho et al. 2011).

Usage

ggseqfplot(
  seqdata,
  group = NULL,
  ranks = 1:10,
  weighted = TRUE,
  border = FALSE,
  proportional = TRUE,
  ylabs = "total",
  no.coverage = FALSE,
  facet_ncol = NULL,
  facet_nrow = NULL
)

Arguments

seqdata

State sequence object (class stslist) created with the TraMineR::seqdef function.

group

A vector of the same length as the sequence data indicating group membership. When not NULL, a distinct plot is generated for each level of group.

ranks

specifies which of the most frequent sequences should be plotted; default is the first ten (1:10); if set to 0 all sequences are displayed

weighted

Controls if weights (specified in TraMineR::seqdef) should be used. Default is TRUE, i.e. if available weights are used

border

if TRUE bars are plotted with black outline; default is FALSE (also accepts NULL)

proportional

if TRUE (default), the sequence heights are displayed proportional to their frequencies

ylabs

defines appearance of y-axis labels; default ("total") only labels min and max (i.e. cumulative relative frequency); if "share" labels indicate relative frequency of each displayed sequence (note: overlapping labels are removed)

no.coverage

specifies if information on total coverage is shown as caption or as part of the group/facet label if ylabs == "share" (default is TRUE)

facet_ncol

Number of columns in faceted (i.e. grouped) plot

facet_nrow

Number of rows in faceted (i.e. grouped) plot

Details

The subset of displayed sequences is obtained by an internal call of TraMineR::seqtab. The extracted sequences are plotted by a call of ggseqiplot which uses ggplot2::geom_rect to render the sequences. The data and specifications used for rendering the plot can be obtained by storing the plot as an object. The appearance of the plot can be adjusted just like with every other ggplot (e.g., by changing the theme or the scale using + and the respective functions).

Experienced ggplot2 users might notice the customized labeling of the y-axes in the faceted plots (i.e. plots with specified group argument). This has been achieved by utilizing the very helpful ggh4x library.

Value

A sequence frequency plot created by using ggplot2. If stored as object the resulting list object (of class gg and ggplot) also contains the data used for rendering the plot.

Author(s)

Marcel Raab

References

Gabadinho A, Ritschard G, Müller NS, Studer M (2011). “Analyzing and Visualizing State Sequences in R with TraMineR.” Journal of Statistical Software, 40(4), 1–37. doi:10.18637/jss.v040.i04.

Wickham H (2016). ggplot2: Elegant Graphics for Data Analysis, Use R!, 2nd ed. edition. Springer, Cham. doi:10.1007/978-3-319-24277-4.

See Also

ggseqiplot

Examples

# Use example data from TraMineR: actcal data set
data(actcal)

# We use only a sample of 300 cases
set.seed(1)
actcal <- actcal[sample(nrow(actcal), 300), ]
actcal.lab <- c("> 37 hours", "19-36 hours", "1-18 hours", "no work")
actcal.seq <- seqdef(actcal, 13:24, labels = actcal.lab)

# sequence frequency plot
# with TraMineR::seqplot
seqfplot(actcal.seq)
# with ggseqplot
ggseqfplot(actcal.seq)
# with ggseqplot applying additional arguments and some layout changes
ggseqfplot(actcal.seq,
           group = actcal$sex,
           ranks = 1:5,
           ylabs = "share") +
  scale_x_discrete(breaks = 1:12,
                   labels = month.abb,
                   expand = expansion(add = c(0.2, 0)))